Ham Radio Help Desk

Irrespective of the fact the solder-the-braid PL-259 connector is probably the worst RF connector conceived by the mind of man¹ and the fact the spark shown in the video is in an area that should be a direct short, the video, shown below, wonderfully shows the ease with which static charge can build up on a dipole antenna.

That’s not the point though. If we were to cut off the connector we would surely still see a spark from center conductor to shield. If the cable were near station ground I would expect a spark jump. That large a charge has to go somewhere.
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Here are some details regarding the next, and probably last, phase of my 43 Foot DX Engineering vertical installation.

This post is very late. The actual date of the events within it are just before March 2009 in preparation for the Virginia QSO Party.

In the many posts within this site, it is no secret my examination of various vertical antenna solutions with comparison between BigIR and the 43 Foot products a big part of this. Check out all the 43 Foot posts on HHD here…
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As my local club in northern Virginia prepares for the March Virginia QSO Party many questions are asked about how best to take full advantage of Near Vertical Incident Skywave (NVIS) communications so critical to maximizing contacts on HF within the state.

In particular one member has a magnificent full wave 160 meter loop up around 50 feet or so. He is contemplating using it for NVIS on 80 meters. He desires to lower it to about 15 feet to improve the NVIS characteristics.

It is true lowering a dipole will focus more energy straight up while reducing the energy towards the horizon. This is a tried and true technique on 80 and sometimes 40 meter NVIS and offers a potential added benefit of less sensitivity to far away thunderstorm noise. This is a method of diminishing returns; Lowering the antenna favors the sky more, but the overall gain is reduced. In other words, less signal is focused in a better NVIS favoring pattern.

Full wave loops are quite different as this EZNEC simulation suggests. Here is a simple four sided loop with 128 foot sides and fed near one corner – just like my friend’s 160 meter loop.
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Doug Adams must have not been an amateur radio operator for he seems to have missed the answer to everything suggesting 42 as the answer to it all.

Perhaps he is right for many things, but for ham radio folks evaluating antenna choices a popular answer for the height of a vertical antenna for the HF bands appears to be 43.

Be sure to check out the many posts about the 43 foot antenna here at Ham Help Desk.
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A company called SteppIR Antennas, Inc. offers a unique solution to the problem of using one antenna for many bands. Their flagship products are Yagi beam antennas for masts that adjust element lengths for frequency, front-to-back ratio, etc. Since they tune dead-on to the desired frequency the Yagi proportions do not ever have to worry about the third Yagi parameter… antenna bandwidth.
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